The long-term goal of the research is to gain a thorough understanding of the factors which regulate the expression of alpha-fetoprotein (AFP) in normal and transformed cells. During development, AFP is synthesized in the yolk sac and liver of the mouse embryo. After birth, the amount of AFP in serum decreases markedly to a basal level which represents less than 0.01% of that in fetal serum. However, reinitiation of AFP synthesis in the adult occurs in liver following injury, in hepatocarcinoma cells, and testicular teratocarcinomas. In addition, a number of congenital birth defects, including congenital nephrosis, severe Rh-hemolytic disease and several open neural tubes defects are associated with increased concentrations of AFP in the maternal and/or fetal circulation and amniotic fluid. In view of the diagnostic value of elevated serum AFP levels in detecting these pathological states in humans, it is clearly important to understand at a molecular level the factors responsible for this elevation. Therefore, I intend to isolate and clone that segment of the mouse genome containing AFP transcribed and flanking sequences which are involved in its regulated expression. The detection of the AFP genomic fragment in the bacteriophage lambda gt WES lambda B vector will be performed using a chimeric plasmid containing a portion of the AFP mRNA sequence, which has been contructed. The genomic segment will be used for extensive sequence analysis of the structure and organization of the AFP transcription unit, and as a substrate for in vitro transcription assays designed to identify the role of RNA, histones, and non-histone chromosomal proteins in the expression of AFP.